Text to Math equation in Python-CodePudding

I'm writing now a pet project in wich I want to draw a plot in terminal window. The idea is that user print an equation, like x = y 1, or 3*x = y. The question is how can I transfom this string equation to equation in Python.

For instance: I have an arraty, for x values like:

x_arr = [1, 2, 3, 4, 5]

And then I want to put it into the user's equation to get y values. or vise versa (vise versa, put y values to get x values)

Thought to create a lot of if conditions and use for loop to detect every characters but it seems smth like sandbox. Is there more elegant way?

CodePudding user response：

You can do it using sympy library.

      from sympy import *
      from sympy.solvers import solve
      x,y = symbols('x,y')
      eq = '3*x=y*2'
      parts = [x.strip() for x in eq.split('=')]
      final_eq = parts[1] '-({})'.format(parts[0])
      equation = Eq(eval(parts[0]),eval(parts[1]))
      x_array = [1,2,3,4,5]
      for x1 in x_array:
            print('given x={}, y={}'.format(x1,solve(equation.subs(x,x1),y)))

Ouput

      given x=1, y=[3/2]
      given x=2, y=[3]
      given x=3, y=[9/2]
      given x=4, y=[6]
      given x=5, y=[15/2]

CodePudding user response：

Use eval for evaluating the textual commands.

https://www.programiz.com/python-programming/methods/built-in/eval